SN　method　is　wildly　used　to　solve　neutron　transport　equation,　but　SN　method　is　very　slow　with　highly　anisotropic　scattering.　In　this　paper,　the　modified　PN　synthetic　acceleration　(MPSA)　method　is　used　to　accelerate　SN　method,　and　applied　to　the　code　of　ANISN　which　is　internationally　used.　MPSA　method　not　only　can　accelerate　the　computation　with　low-order　of　angular　flux　moments,　but　also　with　high-order　of　angular　flux　moments.　So　MPSA　method　is　more　efficient　than　DSA　method.　Numerical　results　for　the　test　problems　demonstrate　that　MPSA　method　is　quiet　efficient　and　robust,　especially　for　the　problems　with　highly　anisotropic　scattering.